How Chia Seeds Can Help With Weight Loss

Like many seeds, chia seeds offer solid nutritional value in the form of beneficial dietary fiber and heart-healthy omega-3 fatty acids. Claims have also been made about chia seeds promoting weight loss. Can chia seeds help you lose weight, or maintain a healthy weight, as you get older?

The Link Between Weight Gain and Aging

Many factors can contribute to weight gain as you age, including hormonal changes, shifts in activity level, and changing muscle mass. A general change in body shape tends to occur in both men and women, with or without weight gain. Lower levels of estrogen after menopause usually lead to more midsection fat in women (not so affectionately known as a "menopot"); in men, hip circumference typically decreases.

If you're less active and burn fewer calories, you'll add on pounds—unless you adjust your caloric intake accordingly.​

Can Chia Seeds Help With Weight Loss? ​

Popular diet books like The Aztec Diet recommend consuming 4 to 8 tbsp (1 to 2 oz, or 30 to 60 g) of chia seeds over the course of the day to keep you less hungry, and less likely to overeat. Because chia seeds absorb up to 10 times their weight in water, proponents say the seeds will help fill up your stomach, and slow the rate at which your body processes whatever you ate at your most recent meal.

Research on Chia Seeds and Weight Gain

For example, a 2009 study of 76 overweight or obese (but otherwise healthy) men and women, published in Nutrition Research, looked at what happened when study subjects consumed 25 g (about 3 tbsp) of whole chia seeds in water, twice a day, before the first and last meals of the day. After 12 weeks, the subjects between the ages of 20 and 70 were measured for changes in body mass, body composition, blood glucose, blood pressure, and other disease markers.

The findings? Body mass didn't change for either the chia subjects or those getting a powder placebo. Despite past research showing that chickens fed chia seed have lower body mass, and rats fed chia have less visceral fat (a type of fat lying deep within the abdomen), the only change in human subjects in this trial, was increased levels of the healthy omega-3 fatty acid alpha-linolenic acid, or ALA.

The scientists write that increasing the daily fiber intake by almost 19 g in the chia group "should have induced a sense of fullness before the morning and evening meals," though no weight loss was observed by the end of the 12-week study.

Similar results were found in a 2012 study of 56 overweight, post-menopausal women, published in the Journal of Alternative and Complementary Medicine. The subjects were given 25 g of whole or ground chia seeds (or poppy seeds as a placebo) for 10 weeks, with body mass, body composition, blood pressure, and other markers measured upon the study's completion. No change in body mass or composition was found in either group.

These findings are in line with those of an earlier small, randomized controlled trial, published in Diabetes Care. After 12 weeks, the 27 subjects—all with well-controlled type 2 diabetes—showed no change in body weight, though there were significant improvements in some cardiovascular risk factors.

Chia Seeds Are No "Magic Bullet" for Weight Loss

David Nieman, Director of Appalachian State University's Human Performance Laboratory, and principal author of both the 2009 and 2012 investigations into chia seeds and weight loss, says there's nothing magic about chia to promote weight loss in older adults.

"There's a lot of nutrition in that little seed, no doubt about it," he tells me. "Chia seeds contain ALA, and they're high in dietary fiber. But that cluster of nutrients doesn't mean they're going to magically do anything in your body."

"Even with such a huge load of soluble fiber—up to almost 19 g extra, each day, in our studies—it appears that even if older people lose a little weight early on, they quickly adapt to the greater fiber load. In the end, there doesn't seem to be any long-term effect on weight loss from chia seeds."

Chia's Ability to Absorb Water​

There's ample nutrition research that suggests water can boost weight loss if consumed in food, rather than simply as a beverage.

Barbara Rolls, a nutrition professor at Pennsylvania State University and an early pioneer of this principle, had this to say when asked if chia's water-absorbent property could—in theory—make it a weight-loss aid.

"If chia soaks up water, it may slow stomach emptying as other water-rich foods do," she observes, though she hasn't studied chia seeds directly. "That can keep you feeling satisfied longer, and therefore less likely to overeat. Still, I don't think we should look to one component, or food, to help us lose weight. Sure: boost vegetable consumption, eat more fiber-rich foods, more water-rich foods, more protein, and lower the overall calorie density of your diet. But no single element in isolation will be as effective as tackling all these aspects of what we eat."

David Nieman agrees. "The bottom line is you have to consume less and burn more, to lose weight at any age," he says. "Chia seeds are nutritious, like many other seeds, but they won't allow you to eat whatever you want."